MPPT charge controller


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I'm working on a concept pocketqube and am currently developing the power management system, I'm looking for the easiest and most efficient way to regulate 3.3v from a battery and charge it using MPPT. I will be using gallium arsenide triple junction cells, It will have a power consumption of under 20ma at 3.3v and needs regulated voltage for the atmega 328p au chip and other IC's, the cells I will be using have a Voltage (Open Circuit) of 2.62 V and Current (Max Power) of 14.6 mA. I have found chips such as the SPV1040 that claim to integrate MPPT circuits, I will need to charge a 3.7v cell (aprox 500Ma). I have a very basic understanding of charging circuits so my question is, are there any efficient MPPT/Battery charge controller IC's on the market or easy to design/already existing devices? Obviously form factor is important since this will be going in a a very reduced space.

All input is deeply appreciated and and collaborations are welcome since working out all aspects of such a project is somewhat complicated.

MPPT only really makes sense if you're charging from a source which is capturing power directly from some fluctuating external source (e.g. wind, solar, wave).

MPPT used from a battery might optimise the fastest charge, but it would not maximise the total energy transferred from the battery, and it would almost certainly cause the battery to get very hot.

Can you explain in more detail what you need to do (rather than how you think you should do it)?
Ok I think I didnt it explain very well , I need to charge a 3.7v battery with solar cells and then output 3.3v for the satellite's components, space is minimal and I have no electrical engineering experience.
Ok. MPPT generally requires that you have a switch mode DC-DC converter controlled by a microcontroller.

At its simplest, it continuously tunes the DC-DC converter to achieve the highest charge current. A more complex circuit may alter the behaviour based on battery voltage, temperature, or state of charge.

In your case I'd probably go looking for an integrated solution - is there a device designed to do all this in a single package? My first search would be for MPPT related items on Digi-Key.

In your second part, producing a 3.3V rail, the simplest approach is a linear regulator, but that's going to generate more heat, which is typically wasted energy. However, if you need to keep the electronics warm, it may even be useful.

You may also need to consider the dropout voltage of your regulator and maybe how much your 3.3V rail is permitted to sag (what is the minimum battery voltage?). An inverting type of DC-DC converter can get you around some of these issues, but you also lose a common ground rail.

I assume you're talking about a cube sat, and in that case, for maximum performance you're going to need to balance a whole lot of things.